Re: What part of z/OS is the OS?
If z/OS doesn't fit a traditional CS definition of a kernel, then what is it? Does the BCP act as a micro or nano kernel with all other services sharing its address space? Does the concept of rings or kernel address space even exist on these machines? -Original Message- From: IBM Mainframe Discussion List [mailto:[EMAIL PROTECTED] Behalf Of Shmuel Metz (Seymour J.) Sent: Monday, August 28, 2006 2:26 PM To: IBM-MAIN@BAMA.UA.EDU Subject: Re: What part of z/OS is the OS? In [EMAIL PROTECTED], on 08/28/2006 at 06:45 PM, Lindy Mayfield [EMAIL PROTECTED] said: Is there a general consensus about what pieces or aspects of the software shipped with z/OS would be defined as the operating system? Well, historically IBM has used the term OS to include everything bundled with the system. Especially since z/OS comes also with a UNIX kernel. Which isn't a kernel in the sense that the CS mean. In fact, it would be hard to find a part of MVS that qualified as a kernel; it really doesn't fit that model. -- Shmuel (Seymour J.) Metz, SysProg and JOAT ISO position; see http://patriot.net/~shmuel/resume/brief.html We don't care. We don't have to care, we're Congress. (S877: The Shut up and Eat Your spam act of 2003) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: What part of z/OS is the OS?
I would venture to say that the operating system as we see it today is a package of a kernel, API, and system utilities. Some would argue that an operating system is only a kernel, and that wouldn't be wrong, just academic. From: IBM Mainframe Discussion List on behalf of Lindy Mayfield Sent: Mon 8/28/2006 12:45 PM To: IBM-MAIN@BAMA.UA.EDU Subject: What part of z/OS is the OS? Is there a general consensus about what pieces or aspects of the software shipped with z/OS would be defined as the operating system? Thing is, I started thinking about what is an OS and I found myself having trouble defining it. For example, for Unix it seems to me that the OS would be the Kernel plus any loadable kernel modules that come shipped with the OS, like drivers for I/O and so on. It probably gets fuzzy when it comes to extensions to the OS. Maybe an equivalent to z/OS would be the shipped SVC's as opposed to vendor supplied? But for z/OS I wasn't how and where to draw the lines. Especially since z/OS comes also with a UNIX kernel. Any thoughts? I was just curious about this. Kind regards, Lindy -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: 27x132?
How do I define a custom logmode? -Original Message- From: IBM Mainframe Discussion List [mailto:[EMAIL PROTECTED] Behalf Of Shmuel Metz (Seymour J.) Sent: Friday, August 18, 2006 3:51 PM To: IBM-MAIN@BAMA.UA.EDU Subject: Re: 27x132? In [EMAIL PROTECTED], on 08/18/2006 at 10:13 AM, Kuredjian, Michael [EMAIL PROTECTED] said: Is it possible to display more than 27x132 characters at a time through a 3270 emulator? Yes. In fact, it's possible on a real 3270 as well. You have three options: 1. Define a custom screen size on your terminal simulator and use a logmode that dynamically picks up the screen size, e.g., D4C32XX3. 2. Define a dynamic screen size on your terminal simulator and use a custom logmode to force the size you want. That's what I used to do on the 3180 and 3192 when I wanted primary 43x80 and secondary 27x132. 3. Define a 3290 on your terminal simulator and use explicit partitions to configure the screen during the session. -- Shmuel (Seymour J.) Metz, SysProg and JOAT ISO position; see http://patriot.net/~shmuel/resume/brief.html We don't care. We don't have to care, we're Congress. (S877: The Shut up and Eat Your spam act of 2003) -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
27x132?
Is it possible to display more than 27x132 characters at a time through a 3270 emulator? -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: 27x132?
I use EXTRA! X-treme... company standard... From: IBM Mainframe Discussion List on behalf of Chase, John Sent: Fri 8/18/2006 10:50 AM To: IBM-MAIN@BAMA.UA.EDU Subject: Re: 27x132? -Original Message- From: IBM Mainframe Discussion List On Behalf Of Kuredjian, Michael Is it possible to display more than 27x132 characters at a time through a 3270 emulator? Absolutely! (Depending on the emulator and application, of course.) Using the Bluezone emulator from Seagull Software, I routinely display 62x160 (3290 emulation). Bluezone also supports arbitrary and capricious screensizes. -jc- -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Anyone using graphical ISPF?
If so, how do you like it? What advantages does it offer over standard ISPF? -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: Anyone using graphical ISPF?
Does anyone know where I can download the installer for windows? The sysadmins for our MF have removed the dataset containing the member required. From: IBM Mainframe Discussion List on behalf of Paul Gilmartin Sent: Thu 8/17/2006 10:46 AM To: IBM-MAIN@BAMA.UA.EDU Subject: Re: Anyone using graphical ISPF? On Thu, 17 Aug 2006 09:58:21 -0400, Kuredjian, Michael [EMAIL PROTECTED] wrote: If so, how do you like it? What advantages does it offer over standard ISPF? No. o It's cumbersome and unesthetic, particularly in the way it formats an EDIT panel with each line appearing as an individual 3-d shaded text entry area. o It requires a specialized display agent running on each display server, rather than employing a portable display protocol such as X11. (Is there an agent available for OS X? Linux (what hardware platforms?) Other (specify)?) o The ATTN key doesn't work. OTOH: o If started from batch it bypasses VTAM restrictions, allowing multiple interactive ISPF sessions for a single user on a single host. o It allows circumvention of certain restricted licenses which limit the number of interactive TSO users. (Don't tell IBM.) -- gil -- StorageTek INFORMATION made POWERFUL -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
WebSphere Developer For zSeries?
I was listening to an IBM podcast on the mainframe, discussing how new developers can easily get into host development through tools like WebSphere Developer For zSeries. Does anyone on this list use that product? If so, do you like it? How did/does it fit into your existing development environment? Can it be made to work with products like CA's Endevor? -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: IBM Redbook: Introduction to the New Mainframe: z/OS Basics
I'm happy you're hiring new grads to work on host systems. The knowledge we (university students) have isn't useless, it just has to be adapted to mainframes. Since universities have long since left that teaching arena, you have two choices left: learn on the job or go through a technical course on mainframe. I find that learning on the job is far more effective. From: IBM Mainframe Discussion List on behalf of Ray Mullins Sent: Fri 7/28/2006 12:01 PM To: IBM-MAIN@BAMA.UA.EDU Subject: Re: IBM Redbook: Introduction to the New Mainframe: z/OS Basics During the zNextGen monthly call yesterday, someone mentioned that the number of z/OS sysprog jobs on Dice has grown a lot in the past few months. Ray -Original Message- From: IBM Mainframe Discussion List [mailto:[EMAIL PROTECTED] On Behalf Of Bob Shannon Sent: Friday July 28 2006 06:45 To: IBM-MAIN@BAMA.UA.EDU Subject: Re: IBM Redbook: Introduction to the New Mainframe: z/OS Basics I do know that we now have a mainframe customer list which is 10% the size it was 10-15 years ago. This is not a discussion about the future of the mainframe, whether the mainframe is a viable platform, or whether there are more windoze licenses than z/OS licenses. It started with this quote There's a great deal of attention now paid to helping new mainframe. IMO, anyone who disputes this hasn't been paying attention. Just for the record, we just hired a 23 year old sysprog right out of college who doesn't know anything about a mainframe - yet. -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: Why is zSeries so CPU poor?
How do we know the number of hardware design errors? With IA32, it's easier to discover these problems because the CPU is used by many people under many operating systems. IBM designs the OS and CPU, making it much easier to cover up any problems that do exist. -Original Message- From: IBM Mainframe Discussion List [mailto:[EMAIL PROTECTED] Behalf Of Bruce Black Sent: Thursday, July 20, 2006 10:46 AM To: IBM-MAIN@BAMA.UA.EDU Subject: Re: Why is zSeries so CPU poor? There are quite a few reasons, rather than just one single one. The biggie IMO is that z architecture is demonically complex to implement in silicon. It has always amazed me that IBM is able to put out a new processor every year or two with little or no hardware logic errors. I know from articles in the technical journals that they do extensive testing, but heck, in the software industry, we do extensive testing and we STILL have to put out a significant number of fixes. Kudos to the hardware developers! -- Bruce A. Black Senior Software Developer for FDR Innovation Data Processing 973-890-7300 personal: [EMAIL PROTECTED] sales info: [EMAIL PROTECTED] tech support: [EMAIL PROTECTED] web: www.innovationdp.fdr.com -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: z/Architecture design errors
I didn't see much cynicism in my comment, although that may be the result of being jaded by my experience with PC manufacturers and their reluctance to admit and correct problems. I'm very used to both hardware and software manufacturers ignoring obvious problems in their products. I may have mis-used the term cover-up. What I meant was that they[IBM] could release software patches that specifically avoid making use of broken circuits in silicon. However, I wasn't aware that mainframe developers routinely make use of micro-assembly instructions, thereby revealing hardware bugs quickly. -Original Message- From: IBM Mainframe Discussion List [mailto:[EMAIL PROTECTED] Behalf Of john gilmore Sent: Thursday, July 20, 2006 11:40 AM To: IBM-MAIN@BAMA.UA.EDU Subject: z/Architecture design errors Michael Kuredjian writes | How do we know the number of hardware design errors? With IA32, it's easier to | discover these problems because the CPU is used by many people under many | operating systems. IBM designs the OS and CPU, making it much easier to cover up | any problems that do exist. IBM does design both, but many others write assembly-language code that exercises these instructions vigorously. Microprocessor assemblers are toys, designed (to quote myself) to discourage their use. The IBM HLASM is a very different, heavily used animal. Mr. Kuredjian's sophomore-cynical comment is, however, wide of the mark in another way. There are two ways to deal with errors in this business. One is to try to keep them secret, fixing them under the covers. The other is to call a shovel a spade as quickly as it has been identified in order to turn one's back upon it as quickly as possible. IBM does the second. The trouble with the first approach is that when, inevitably, dissimulation is detected, it becomes a cause celebre. Even Microsoft learned, after a time, that candor about the security deficiencies of Windows was the only feasible approach. It now has its hand held in the fire much more briefly than used to be the case. It is perhaps also worth noting that, while software errors are expensive, hardware errors are even more expensive and much more embarassing. It is much cheaper to find them before they get into silicon. John Gilmore Ashland, MA 01721-1817 USA _ Don't just search. Find. Check out the new MSN Search! http://search.msn.click-url.com/go/onm00200636ave/direct/01/ -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: Newbie Questions!
Thanks to all of those that are replying. I've found a wealth of information in the IBM RD website. They have an issue that details the architecture of the z990 CPU very clearly. It seems as through IBM is modernizing the arch to handle more OOE/Superscalar execution as they make a push to SOA and e-business models. Out of curiosity, I've started poking around the system I've access to through ISPF to find out more regarding the hardware. Through the ISPVCALL STATUS function, I found that the system I'm on is a zArch 2064 with 4 CPUs; however, is there a way I can retrieve the model # of this system as well? -Original Message- From: IBM Mainframe Discussion List [mailto:[EMAIL PROTECTED] Behalf Of Tom Marchant Sent: Wednesday, July 19, 2006 10:35 AM To: IBM-MAIN@BAMA.UA.EDU Subject: Re: Newbie Questions! On Tue, 18 Jul 2006 15:46:27 -0400, Kuredjian, Michael [EMAIL PROTECTED] wrote: I'm currently in University on my Co-op term as a COBOL programmer for host systems (zOS). I have a few basic questions regarding the zArchitecture that I can't seem to elicit answers to from my co-workers. The questions are as follows: 1. zOS has a kernel called the BCP, or Base Control Program. In Linux or Windows, it's established that the kernel runs on a general purpose CPU( PowerPC, x86, MIPS, etc...); however, I would like to know if such a central CPU exists in the mainframe, and if that central CPU is of some common architecture like, POWER. If not, are there any documents that I can look into that will describe the CPU architecture for me? While the processor has been enhanced over the years, the CPU may be the first general purpose architecture still in existence. The 360 architecture is still an integral and important part of z/Architecture, and almost any program written for 360 will run without being modified on z/Architecture. 2. ESCON and FICON are data busses used for external storage devices, but what does the mainframe use for internal data bus, InfiniBand, HyperTransport? IBM doesn't make the internal details available. In order to perform, there is a lot of point-to-point interconnect. Paths to memory are very wide, again to improve performance. I can't seem to find the last reference I found, but I think it's 256 bytes. FICON is essentially Fibre Channel with extra layers to improve security. 3. Does the mainframe use common interconnects on the hardware level? I'm thinking of PCIe, PCI-X, MCA, or PCI. AS someone mentioned, there are PCI slots for cryptographic processors, but for general use, none of those is fast enough. Connections from memory to the channels is through 16 Self Timed Interconnect (STI) busses per book (a maximum of 64), each of which is capable of independently transferring 2.7 Gigabytes per second. The z9 EC can support up to 336 FICON channels, and STI is how the data is transferred between the channels and memory. The channels on the mainframe do not talk directly to devices, but to control units, which are specialized processors that relieve the processor of the details of most of the workings of the device. There are tons of details on the IBM web site. Try these, for example: http://www-03.ibm.com/systems/z/hardware/ http://www-03.ibm.com/servers/eserver/zseries/zos/ Good luck, and welcome to the platform! Tom Marchant -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: Heh. Speaking of Java
Is there an easy way to view the stacktrace? -Original Message- From: IBM Mainframe Discussion List [mailto:[EMAIL PROTECTED] Behalf Of Jon Brock Sent: Wednesday, July 19, 2006 11:24 AM To: IBM-MAIN@BAMA.UA.EDU Subject: Heh. Speaking of Java I'm trying to research why I am getting a java NullPointerException when I try to start up Tomcat on z/OS. I go to IBM developerWorks, which wants a screen name. I put in a screen name, click Submit, and I get -- ta da! -- a NullPointerException. Thanks, guys, but what I wanted was information about the NPE, not another actual NPE. I can get one of those any time I feel like it. sigh Jon -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: Why is zSeries so CPU poor? (was:RE: Linux - Our Saving Grace?)
Does IBM make a co-processor add-in that can provide an assist for the JVM overhead? -Original Message- From: IBM Mainframe Discussion List [mailto:[EMAIL PROTECTED] Behalf Of McKown, John Sent: Wednesday, July 19, 2006 1:10 PM To: IBM-MAIN@BAMA.UA.EDU Subject: Why is zSeries so CPU poor? (was:RE: Linux - Our Saving Grace?) Just out of curiousity, why is the zSeries CPU so poor at CPU-intensive workloads, like Java? Is it the clock speed of the circuitry? Is it the complexity of the instructions? Is it the fact that the machine does a lot of internal checking / checkpointing for reliability and recovery? -- John McKown Senior Systems Programmer HealthMarkets Keeping the Promise of Affordable Coverage Administrative Services Group Information Technology This message (including any attachments) contains confidential information intended for a specific individual and purpose, and its content is protected by law. If you are not the intended recipient, you should delete this message and are hereby notified that any disclosure, copying, or distribution of this transmission, or taking any action based on it, is strictly prohibited. -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: Linux - Our Saving Grace?
Linux can have a small memory foot print. As far as I know, much of the size of a kernel image comes from statically compiled modules. If space is a concern, it's perfectly feasible to omit many kernel modules from the build process and only keep those required as modules. -Original Message- From: IBM Mainframe Discussion List [mailto:[EMAIL PROTECTED] Behalf Of SUBSCRIBE IBM-MAIN tdell Sent: Wednesday, July 19, 2006 1:33 PM To: IBM-MAIN@BAMA.UA.EDU Subject: Re: Linux - Our Saving Grace? I could bet the farm that's ECLipz , is code name for hardware emulation at the micro/milli code level. The new architecture could be framed like the CELL expecting one or more 390 CPU's married to a network of CELL processors , which in turn is supported by several other RISC processors to handle the various workloads and emulation. The major task of instruction decoding, and memory fetching can be done by another processor on behalf of the 390 CPU. That is a BIG portion of the heavy lifting required to execute a program. That's a lot of machine cycles saved, that's why RISC CPU's can boast they don't have those performance penalties to contend with, since it's somewhat separated out of the normal decoding behavior. Some 12 years ago,I initially believed the Linux having such a small kernel in it's early life had a distinct advantage of other OS's, but I was incorrect (and somewhat naive and misinformed) on how it would have performed on RISC versus the INTEL (386/486) implementations. The numbers do bear that out but I don't have much of an interest in that area any more since I back working exclusively with mainframes. I'm still a UNIX hobbyist and run both AIX and Linux at home, utterly frustrating and fun at the same time. If anyone out there know(Z) please tell me I'm still curious about where this is all going. Be A RISC based line of 390 CPU's or POWER like CPU with a 390 emulation. Good info on the thread -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: Why is zSeries so CPU poor?
Does zLinux have a kernel patch that allows it to offload the JVM to this co-proc when running in an LPAR? -Original Message- From: IBM Mainframe Discussion List [mailto:[EMAIL PROTECTED] Behalf Of Edward Jaffe Sent: Wednesday, July 19, 2006 1:48 PM To: IBM-MAIN@BAMA.UA.EDU Subject: Re: Why is zSeries so CPU poor? Kuredjian, Michael wrote: Does IBM make a co-processor add-in that can provide an assist for the JVM overhead? zAAPs -- Edward E Jaffe Phoenix Software International, Inc 5200 W Century Blvd, Suite 800 Los Angeles, CA 90045 310-338-0400 x318 [EMAIL PROTECTED] http://www.phoenixsoftware.com/ -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: Why is zSeries so CPU poor?
It's an interpreted language. -Original Message- From: IBM Mainframe Discussion List [mailto:[EMAIL PROTECTED] Behalf Of Goforth, Mark Sent: Wednesday, July 19, 2006 1:56 PM To: IBM-MAIN@BAMA.UA.EDU Subject: Re: Why is zSeries so CPU poor? zAAPs do not work under zLinux. They only work under zOS. As for Java, the more appropriate question might be why is it so inefficient? This email and any files attached with it are confidential and intended solely for the use of the individual or entity to whom they are addressed. If you have received this email in error delete this message and notify the sender at 402-341-0500. If you are not the named recipient you should not disseminate, distribute or copy this email or any attachment. -Original Message- From: IBM Mainframe Discussion List [mailto:[EMAIL PROTECTED] On Behalf Of Kuredjian, Michael Sent: Wednesday, July 19, 2006 12:53 PM To: IBM-MAIN@BAMA.UA.EDU Subject: Re: Why is zSeries so CPU poor? Does zLinux have a kernel patch that allows it to offload the JVM to this co-proc when running in an LPAR? -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Re: Why is zSeries so CPU poor?
Correct. The byte code generated by the Java compiler isn't understandable by any machine except the Java Virtual Machine. The JVM interprets this object code and relays the calls to those found in the host system's API. Out of curiosity, how does C++ perform on zOS? -Original Message- From: IBM Mainframe Discussion List [mailto:[EMAIL PROTECTED] Behalf Of McKown, John Sent: Wednesday, July 19, 2006 2:03 PM To: IBM-MAIN@BAMA.UA.EDU Subject: Re: Why is zSeries so CPU poor? -Original Message- From: IBM Mainframe Discussion List [mailto:[EMAIL PROTECTED] On Behalf Of Kuredjian, Michael Sent: Wednesday, July 19, 2006 12:59 PM To: IBM-MAIN@BAMA.UA.EDU Subject: Re: Why is zSeries so CPU poor? It's an interpreted language. Again, not really. The Java source code is actually compiled to a binary form which is called Java Byte Code. This byte code is similar in nature to a normal processor's instruction set. I guess you could say that the JVM inteprets the byte code. But I think of it more like the JVM includes a byte code emulator (like the old 1401 emulator). But, from what I can tell,the Java byte code doesn't match the zSeries instruction set very well. So it is relatively inefficient. -- John McKown Senior Systems Programmer HealthMarkets Keeping the Promise of Affordable Coverage Administrative Services Group Information Technology This message (including any attachments) contains confidential information intended for a specific individual and purpose, and its content is protected by law. If you are not the intended recipient, you should delete this message and are hereby notified that any disclosure, copying, or distribution of this transmission, or taking any action based on it, is strictly prohibited. -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
Newbie Questions!
I'm currently in University on my Co-op term as a COBOL programmer for host systems (zOS). I have a few basic questions regarding the zArchitecture that I can't seem to elicit answers to from my co-workers. The questions are as follows: 1. zOS has a kernel called the BCP, or Base Control Program. In Linux or Windows, it's established that the kernel runs on a general purpose CPU( PowerPC, x86, MIPS, etc...); however, I would like to know if such a central CPU exists in the mainframe, and if that central CPU is of some common architecture like, POWER. If not, are there any documents that I can look into that will describe the CPU architecture for me? 2. ESCON and FICON are data busses used for external storage devices, but what does the mainframe use for internal data bus, InfiniBand, HyperTransport? 3. Does the mainframe use common interconnects on the hardware level? I'm thinking of PCIe, PCI-X, MCA, or PCI. That's all for now, but I'm sure subsequent answers will generate follow-up questions on my part. Thanks for taking the time to read this! -- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
